Performs textual search on the sidebar

<div class="definition">
    search(str)
</div>

<div class="arguments">
    <table>
    <tr>
        <td>str</td>
        <td><b>string</b>, text to search</td>
    </tr>
    </table>
</div>
Returns <i>undefined</i>.

<h4>Description</h4>

This method will search all nodes of the sidebar and those that match search criteria will be made visible, those that are not will be made hidden.
<div style="height: 10px"></div>

If you have sidebar defined in the following way:
<textarea class="javascript">
let sidebar = new w2sidebar({
    name : 'sidebar',
    img  : 'icon-page',
    nodes: [
        { id: 'id-1', text: 'Level 1' },
        { id: 'id-2', text: 'Level 2 (txt)' },
        { id: 'id-3', text: 'Level 3' }
    ]
});
</textarea>

You can:
<textarea class="javascript">
w2ui.sidebar.search('txt')
// to clear search
w2ui.sidebar.search()
</textarea>
